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Check engine light

Have a 1999 Jeep Grand Cherokee 4.0.
Check engine light will not go off.
It came on when the cooling fan relay went out, I replaced the relay and the complete cooling fan assembly. Removed battery cables to clear light, 5min, then 10 min.then 30 min. no luck still stayed on. Thought may be it could be a defective relay, but that was not the case. It still stays on.
Traced the wire from the relay from the wiring harness to the fire wall,
to the dash gauge assembly, to the circuit board for the light bulb, for the check engine light, and with key in on position it has a hot wire to the bulb circuit.
I have a scanner and on I/M Readiness it shows MIL Off, and on Drive Cycle it shows MIL Off? The scanner shows no codes, or no stored codes?
The stupid light still stays on?
Any help. Thanks.

__________________Steering stabilizers will not cure or cause death wobble, they only mask the real problem that is causing death wobble. Oil pumps do not make pressure, they create flow. Bearing clearence and restrictions make pressure. It's the crank sensor.

__________________Steering stabilizers will not cure or cause death wobble, they only mask the real problem that is causing death wobble. Oil pumps do not make pressure, they create flow. Bearing clearence and restrictions make pressure. It's the crank sensor.

There is a long troubleshooting tree to follow before condemning the PCM. A dealer or a Jeep specialist would be the best bet for proper diagnosis.

__________________Steering stabilizers will not cure or cause death wobble, they only mask the real problem that is causing death wobble. Oil pumps do not make pressure, they create flow. Bearing clearence and restrictions make pressure. It's the crank sensor.

Only disconnecting the battery cables will most likely not shut the light off. Try disconnecting the positive cable, jump it to the negative then turn the key on then turn your headlights on for a sec then all off. Reapply the positive terminal and see if the lights off. This process discharges the capacitors in the pcm, clearing all codes and mil light as long as there is no issue. This is known as the chrysler pcm reflash, although technically its just a hard reset

That should work, however you'll have to reset your radio memory, clock, and the PCM will have to relearn your driving habits. Small price to pay.

__________________
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I did take it to the Jeep dealer, and they said it was the PCM, that the new
cooling fan relay,under the right headlamp assembly was not commuicateing
with the PMC circuit, and to replace the PCM, it was defective.

I did take it to the Jeep dealer, and they said it was the PCM, that the new
cooling fan relay,under the right headlamp assembly was not commuicateing
with the PMC circuit, and to replace the PCM, it was defective.

But did you check for specific communication to the pcm or just the relay to the guage?

Now have a problem not starting.
Engine turns over, but will not start.
Turn key to on position, and the check gauges light stays on,
fuel light stays on, and security key light stays on.
Tried the on off , on off and on off, to make sure the security systems
cleared, checked all fuses and relays under hood and dash, again,
has full tank of gas.
Could the PCM finely died?